red giant (redirected from Red giants)

red giant

n.

A star of great size and brightness that has a relatively low surface temperature.

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red giant

A giant star that has a relatively low surface temperature, giving it a reddish or orange hue. Red giants are non-main-sequence stars positioned in the upper right of the Hertzsprung-Russell diagram. They are not massive stars but rather late, expanded stages of lower-mass main-sequence stars that have exhausted the hydrogen in their core and are fusing their remaining hydrogen into helium in a luminous outer shell. The Sun is expected to become a red giant in about 5 billion years, expanding to 70 times its current size and bringing its surface extremely close to Earth's present orbit. See more at star. See Note at dwarf star.

Thesaurus

Noun

1.

red giant - a large, old, luminous star; has a relatively low surface temperature and a diameter large relative to the sun red giant star star - (astronomy) a celestial body of hot gases that radiates energy derived from thermonuclear reactions in the interior